Improvement in shuttles for sewing-machines



1 W. H. S'GHDFIELD.

Shuttles for Sewing-Machines.

No. 143,303I Patente'dSeptember30,l873.

INVENTOB UNITED STATES PATENT OEEIGE.

WILLIAM H. SGHOFIELD, OF SOMERVILLE, ASSIGNOR OF ONE-HALF HIS RIGHT TOV JOHN F. DONNELL, OF OAMBRIDGEPORT, MASSACHUSETTS.

IMPROVEMENT IN SHUTTLES FOR SEWING-MACHINES.

Specification forming part of Letters Patent No. 143,303, dated September 30, 1873; application filed April 11, 1873.

To all whom t may concern:

Be it known that I, WILLIAM H. Sono- FIELD, of Somerville, in the county of Middlesex and State of Massachusetts, have invented certain Improvements in Sewing-Machine Shuttles, of which4 the following is a specification My invention relates to the mechanism of the shuttle for obtaining the tension on the thread; the object of my invention being to obtain a regular and reliable tension.

Figure 1 shows a plan of the shuttle in reverse position. Fig. 2 shows an elevation of one side..of the shuttle in working position. Fig. 3 shows an elevation of the other side of the shuttle in reversed position, having the tension-spring in working position in relation to the shuttle. Fig. 4 shows the same side as Fig. 3, but with thetension-spring thown up.

`A is the shuttle; B, the bobbin. D is the tension-spring. This spring is pivoted at f to swing, as shown, and hooks, when in working position, into a slot, g, whereby it is held in place and gives the required pressure upon the thread. The thread h passes through one or more of the holes d, or alternately through the slot e' and holes d, according to the amount of tension required, and then passes between the spring D and the side of the shuttle, taking the direction shown.

The use of the spring D insures the necessary even tension and at the proper place. The spring D being naturally harder than it is practicable to make the body of the shuttle, makes the shuttle more durable in its wearing-surface, since this hardened spring acts as part of one bearing side of the shuttle.l 

